Frequently Asked Questions (FAQs)

What is Rule 1180?

Rule 1180 was adopted in December 2017 by the South Coast AQMD, mandating real-time observations of important air pollutants at the fenceline of all large petroleum refineries in the South Coast Air Basin (Basin), and in nearby communities.  Refineries that produce 40,000 gallons of crude oil or greater are required to conduct this type of monitoring continuously and in near-real time and display this information on a dedicated website.  Rule 1180 also establishes fee for which South Coast AQMD will conduct monitoring at nearby community sites.

Rule 1180 satisfies the larger state-wide California Assembly Bill No. 1647, which requires refineries to maintain fenceline monitoring systems, and the development of refinery-related community monitoring sites.

More information on Rule 1180 can be found here.

Who is performing these measurements?

The community air monitoring sites are established, maintained and operated by the South Coast AQMD.  

The refineries are responsible for installing and operating the fenceline monitoring systems and are allowed to rely on outside contractors for operating these systems.  They are required to submit Fenceline Air Monitoring plans to the South Coast AQMD for approval.  Partial approval of these plans was granted in March and April of 2019.

The most recent versions of the Refineries Fenceline Air Monitoring plans can be found here.

What compounds are measured under Rule 1180?

The following is the list of pollutants that are required to be measured under Rule 1180. 
For additional information about the compounds being monitored, please see Appendix A2 of the CAMP.

Pollutant_Table_Criteria Pollutants
Pollutant_Table_Other Compounds

How often are the data on the website updated?

The measurement data displayed on the website are updated every 5 minutes and are based on 5-minute average and 1-hour rolling average concentrations.

What are Reference Exposure Levels (RELs)

The reference exposure level (REL) is the concentration below which no adverse health effects are anticipated for a certain amount of exposure time: acute REL is based on 1-hour averages, 8-hour REL is based on 8-hour averages, and chronic REL is based on exposure over a human lifetime. Because the data collected by the fenceline and community sites are near-real time, it is appropriate to compare them to the acute 1-hour REL. RELs are based on relevant, adverse health effects reported in the medical literature. RELs are set by the California Office of Environmental Health Hazard Assessment (OEHHA), For more information visit OEHHA website.

What will happen if an air pollutant monitoring system is down?

In case of an unexpected break down or maintenance real-time air monitoring system will be fixed as soon as possible.  A detailed list of backup measures that will be implemented in case of instrument break down, malfunction, or maintenance will be provided in the CAMP’s Quality Assurance Project Plan (QAPP; currently under development).

Ask the Rule 1180 Monitoring Team
Rule 1180
Newsletter Sign Up
Periodic newsletter updates via Email on a variety of air quality-related topics

South Coast Air Quality Management District

21865 Copley Dr, Diamond Bar, CA 91765


© 2024 South Coast Air Quality Management District